CN1370217A - Catalytic cellulignin fuel - Google Patents

Abstract

The present invention relates to a catalytic cellulignin fuel obtained by a biomass pre-hydrolysis process and that is composed of cellulose and globulized lignin with a specific surface of about 1.5 - 2.5 m2/g. The cellulignin fuel according to the invention may be ground down to particles smaller than 250 mu m and has a combustion heat value that can reach up to 18 to 20 MJ/kg and an ignition time equal to or shorter than 20 ms (0.02s).

Description

Catalytic Cellulose Lignin Fuel

field of invention

The present invention relates to a new fuel obtained from biomass.

Background of the invention

From an energy point of view, obtaining energy from biomass is of high value. For example, the energy efficiency of so-called short-rotation biomass reaches 89.5%, and the liquid energy rate is also as high as 9.48 times. However, despite this biomass's surprisingly high energy efficiency, it still cannot compete with fossil fuels. This is due to the number of steps involved in its production, which is costly and also due to the difficulty of disposing of raw biomass, which makes it very impractical.

Attention should be paid to the following points related to biomass production methods: 1) planting and cultivation (propagation); 2) nourishment (fertilization) cost; 3) sunlight exposure; 4) temperature; 5) precipitation; 6) soil and water 7) harvesting methods; 8) disease tolerance; 9) competition in acreage with food, forage and fiber production; 10) area availability; 11) delivery of raw biomass.

Biomass is composed of cellulose, hemicellulose and lignin, its composition is illustrated in Table 1, and its microstructure is shown in Figure 1.

Table 1 cell wall Typical Composition - Pine (%) Hemicellulose Cellulose lignin LM-Medium - - 3.0 P-primary wall 1.4 0.7 8.4 S-secondary wall S1 3.7 6.13 10.5 S2 18.4 2.7 9.1 S3 5.2 0.8 total 28.7 40.3 31.8

The cell wall is composed of macrofibrillae, microfibrils, micelles and cellulose molecules. The nucleus (cytoplasm) includes the aqueous solution. The following chemical formula is equivalent to an approximate estimation formula for the biomass specific surface area (area per unit mass) assuming that the biomass is fully released in its microstructure.

胶束宽度b＝10μm细胞壁厚度：e＝1.0μm1 - Geometry with square section and length 1 (S and M: cell surface and cell mass). S=4bl; M=4blep

Micelle width b = 10 μm Cell wall thickness: e = 1.0 μm

ρ=1.5g/ ^cm3

=1.5×10 ⁶ g/cm ³ .

2. The specific surface area of giant fibers, micro fibers, micelles (miscellae) and cellulose molecules. S = πφl;

2.a The specific surface area of giant fibers (φ=50nm; macropores>50nm) $\frac{S}{m}=\frac{4}{50\×{10}^{-9}\×1.5\×{10}^6}=53m^2/g$

2.b-Specific surface area of microfiber (φ=50/4=12.5nm; mesopore 2nm<φ<50nm) $\frac{S}{m}=\frac{4}{12.5\&times;{10}^{-9}\&times;1.5\&times;{10}^{-6}}=213m^2/g$

2.c-micelle (φ=(12.5/4)nm=3.1nm; micropore φ<2.0nm) specific surface area) $\frac{S}{m}=\frac{4}{3.1\&times;{10}^{-9}\&times;1.5\&times;{10}^6}=860m^2/g$

2. The specific surface area of ((3.1/6)nm=0.517nm) of d-cellulose molecule $\frac{S}{m}=\frac{1}{0.517\&times;{10}^{-9}\&times;1.5\&times;{10}^6}=1290m^2/g$ $N=1+6\underset{0}{\overset{\mathrm{no}}{\mathrm{\&Sigma;}}}\mathrm{ni}=1,(1+6=7),(1+6+12=19),(1+6+12+18=37).$

The theoretical specific surface area of the micelles is about 0.7 m ² /g, the value of the macrofibrils is about 50 m ² /g, the microfibrils are about 200 m ² /g, the micelles are about 900 m ² /g, and the molecules are about 1300 m ² /g.

As far as solid fuels are concerned, the conventional combustion of solid fuels includes five zones: the first zone, the non-reactive solid zone (heating and drying); the second zone, the reaction zone in the condensed phase (solid pyrolysis) ; The third zone, the gas phase reaction (gas phase high-temperature pyrolysis and oxidation) zone; the fourth, the primary combustion zone (gas phase); the fifth, the post-flame reaction zone (secondary combustion). The specific kinetics and reactions of each zone are not fully known.

Figure 2 illustrates a conceptual model of conventional combustion of wood. Wood is anisotropic and absorbent, and its fibers (tracheids) are hollow. For softwood, the fiber length is 3.5-7.0mm, for hardwood, the fiber length is 1-2mm. Its bound water is about 23%, and the total moisture reaches 75%. Cellulose, hemicellulose and lignin behave like polyalcohols in which the main functional groups are OH groups. Cellulose is a linear polysaccharide of anhydroglucose with 1 to >4 β-glycosidic linkages. After oxidation, such functional groups are carbonyl, keto and carboxyl groups. On the other hand, hemicellulose is a branched polysaccharide whose main component is 4-O-methylglucose-p-benzylphenylcarboxamides (4-O-methylglucoroxylanes) in hardwood, and in In cork are glucomanes. Their main functional groups are carboxyl, methyl and hydroxyl groups. In yet another aspect, lignin is a three-dimensional framework with 4 or more substituted phenylpropane units. The basic structural blocks are guayaquil alcohols (softwood) and seringyl alcohols (for both woods), the predominant linkage being β-O-4.

The structure of cellulose and lignin is highly oxygenated, and the position of functional groups is useful for speculating on the mechanism of high temperature pyrolysis and oxidation.

For comparison, it was observed that the silk coal structure is aromatic, with a small amount of hydroxyl functional groups and β-O-4 bonds. Nitrogen and sulfur are part of structural rings, and a small amount of nitrogen exists as an amine. The fact that coal has an extremely low oxygen content compared to wood is evident in the greater reactivity of wood.

In the conventional combustion of wood, the drying stage actually includes 4 steps, that is, 1) the energy required to heat the wood up to 100°C (373K) = 0.08×100×(1-TU)kJ/kg, where TU is the Amount of water (percentage); 2) Energy required to heat water = 4.2 x 100 kJ/kg; 3) Energy required to vaporize water = 2.26 MJ/kg; and 4) Energy required to release bound water 15.5 x TU kJ/kg kg (average). The main part of the value is the energy to vaporize the water.

The heating stage includes three factors that have a significant impact: the first factor is the energy required for heating to the pyrolysis temperature (500-625°K); the specific heat of wood at 273°K is 1113J/g and at The specific heat at 373°K is 1598 J/g, while the specific heat at 300°K of wood with a humidity of 35% is 2.343 J/g. Second, moisture has an effect on preventing the core from being heated to a temperature at which water vaporizes and establishing a reactive state. A third influencing factor is that moisture increases the thermal conductivity of wood particles, which can at most double its value. In addition to the effect on drying and heating, moisture also has a significant effect on solid-state pyrolysis.

The next stage is the solid pyrolysis step. In this combustion zone, reactions of fragmentation of molecules into gaseous fragments and condensation reactions predominate, resulting in coal (tar gives 3 final fractions: gas, liquid and solid - coal). The pyrolysis temperatures are: hemicellulose (500-600°K), cellulose (600-650°K) and lignin (500-773K). Table 2 shows that the pyrolysis products of cellulose and xylan, which have high tar content, cause wood secondary combustion close to oil. Table 2: High temperature pyrolysis products of cellulose (837°K) and xylan (773°K) product Cellulose (%P) Xylan (%P) Acetaldehyde 1.5 2.4 Acetone propionaldehyde 0.0 0.3 Furans 0.7 Tr Acryl alcohol 0.8 0.0 Methanol 1.1 1.3 2-Methylfuran Tr 0.0 2,3-Butanedione 2.0 Tr 1-Hydroxy-2-propyl-glycoxal 2.8 0.4 Acetic acid 1.0 1.5 2-furfural 1.3 4.5 5-methyl-2-furfural 0.5 0.0 CO ₂ 6.0 8.0 H ₂ O 11.0 7.0 coal 5.0 10.0 tar 66.0 64.0

Tr = trace

Aromatic ring cleavage is an intermediate step, forming volatile materials, yielding acetic acid and acetaldehyde, which are decarboxylated by acetic acid ( ) and acetaldehyde decarburization ( ) were decomposed. For hemicellulose, _the resulting products are _C2H4 and CO from propanol. In the next zone, high temperature pyrolysis and oxidation will occur sequentially, producing CH ₄ , C ₂ H ₄ , CO and CO ₂ as final products.

The high-temperature pyrolysis of lignin is different from hemicellulose and cellulose, and it produces the following components at 823K: coal (55%), from CO (50%), CH ₄ (38%), CO ₂ (10%) ) and C ₂ H ₆ (2%) gas fraction (45%). Tar is composed of phenylacetylene, anthracene and naphthalene. Table 3 shows the formation of coal in the high temperature pyrolysis of several different materials. Table 3: Coal formation during high temperature pyrolysis of several different materials (673K) Material Coal (%p) Cellulose 14.9 Poplar (wood) 21.7 Larch (wood) 26.7 Aspen (branch) 37.8 Douglas (bark) 47.1 Lignin sulfate 59.0

Moisture also has a strong influence on the pyrolysis of particles, as it induces a large temperature difference (400°K) between the core and its periphery, creating a physical separation between the heating and drying zone and the pyrolysis zone. The dominant effect of moisture is to reduce the flame temperature of the burner, promote the formation of coal and reduce the rate of high temperature pyrolysis. The theoretical flame temperature for wood combustion is given by:

Ta＝1920-(1.51[TU/(1-TU)]×100)-5.15 X _exAr

Where Ta(K) is the adiabatic flame temperature, TU is the water content fraction, and X _exAr is the percentage of excess air. In addition to the decrease in adiabatic temperature, the excess air volume also increases, which is given by:

X _exAr (%)＝40[TU/(1-TU)]

For TU > 33%, Ta = 1740°K; and for TU = 50%, Ta = 1560°K. Therefore, the volatile content decreases and the coal content increases. Finally it should be noted that ash lowers the local temperature and catalyzes coal formation.

Second, a pre-combustion reaction occurs, which represents fragmentation of the volatile material by a chain-initiated type reaction dominated by free radicals:

(368 kJ/mol)

(410 kJ/mol)

_where R= _C2H5 , _CH3 , etc. R" = methyl group.

In wood, the first reaction is most likely because of its lower energy, as follows:

where M is the particle or molecule (ash or vapour) that removes heat. If R" contains two or more carbon atoms, it is preferred to break the CC bond rather than the CH bond. In addition to the chain initiation reaction, the pre-combustion zone includes a reduction reaction with free radical recombination, . Especially if the pre-combustion zone is spacious. An example of this is the recombination of nitrogen, forming _N2 instead of NOx.

After the pre-combustion reaction, the primary combustion reaction occurs: the oxygen and fuel mixed in the primary combustion zone lead to many reactions of free radicals, producing CO ₂ and H ₂ O.

HCO and CO are formed from CH ₂ O ( or ). Their concentration is greatest at the flame temperature of 1320K, which is the burning temperature of wood.

Finally, an afterburning reaction occurs: the process of burning wood occurs at low temperatures, and the chain termination reaction occurs in a secondary combustion. Hydroxyl radicals (CH ₂ O) are of great significance when present in high concentrations. The main termination reactions are:

The latter is less important in this area. _CO2 production from CO is controlled by OH concentration, which is higher for low temperature systems (wood). Thus, chain termination is the recombination of H with OH groups, facilitated by the exothermic species (M). The C:H ratio of softwood (1:1.45) and hardwood (1:1.37) are higher than that of silk coal (1:017). High-temperature pyrolysis of wood solids produces water, CH ₄ , C ₂ H ₄ and C ₂ H ₆ , which produces a large amount of hydrogen in volatile gases and increases the concentration of hydroxyl groups that can fully and rapidly oxidize (higher reactivity). Due to the many variables associated with the oxidation of wood volatiles, the literature lacks a complete representation of this system.

In the combustion of (wood) activated carbons, activated carbons obtained from high-temperature pyrolysis are porous and contain various free radicals attacked by _O2 . In addition, it also contains oxygen and hydrogen, and its empirical chemical formula is C6.7H.3.3O. For activated carbon oxidation, three mechanisms have been proposed, and the limitation of the combustion rate by the active sites of surface radicals is the accepted mechanism. Activated carbon oxidation is also limited by mass transfer processes. The first mechanism is the Boudouard mechanism, generally marked by activated carbon combustion.

This reaction is a highly endothermic reaction, and the reaction constants are: 1.1×10 ^-2 (800K) and 57.1 (1200K). The released CO is a volatile substance whose combustion is accomplished in an extraparticle flame. The second mechanism is the chemisorption of _O2 directly on the coal. On the coal porous surface, the adsorption activation energy of O ₂ is in the range of 54-10105 kJ/mol, which corresponds to the chemisorption amount of 0-0.25 moles of O ₂ per gram of coal, respectively. The chemical adsorption reaction is:

The asterisk * indicates the active site of the reaction, m indicates the mobile species, and es indicates the stable species. Activated carbon active sites can be generated through a high-temperature pyrolysis mechanism. Activated carbon oxidation as a third mechanism involves the generation of hydroxyl groups in the active sites via the following reactions:

Hydroxyl groups are generated internally by the homolysis of various hydroxyl functional groups in wood or the dissociation pathway of fuel to release water. The effect of moisture on coal oxidation, as in the case of wood pyrolysis, is not well understood. It is speculated that the moisture "strips" the active sites, thereby reducing the rate of oxidation of the coal. The presence of moisture retards the oxidation rate of activated carbon.

In brief, wood combustion is a multi-stage process involving heating and drying, solid state pyrolysis, generation of volatile compounds and coal, gas phase reactions (pre-combustion, primary combustion and post-combustion) and combustion of coal. Various functional groups in wood produce a large number of volatile products belonging to high-temperature pyrolysis of granular solids. Various functional groups and high aliphatic content increase the reactivity of wood, making the flame part of wood burning higher than that of silk coal. Moisture increases the thermal conductivity, resulting in more coal produced in solid-state high-temperature pyrolysis, which increases the concentration of hydroxyl groups in the gas phase reaction and coal reaction, reduces the oxidation rate of coal, and then reduces its temperature and "removes" the active site.

Due to the complexity and operational disadvantages of conventional combustion methods, it would be desirable to develop a new fuel from biomass which fulfills this basic requirement for combustion and overcomes the technical disadvantages of known fuels.

In this regard, various studies on the development of new fuels from biomass have been carried out and have already tried to provide some satisfactory results, such as by Daltro G. Pinatti, Christian A. Vieira, Jose A. da Cruz and Rosa A. Conte As in the case of the cellulosic lignin fuel described in the article "Cellulosic Lignin: A New Thermoelectric Fuel" by et al., involving a non-optimized control of a common cellulosic lignin product obtained through a biomass prehydrolysis process . However, it is still desirable to obtain fuels by more advanced methods, mainly from an economic point of view and also from the point of view of being able to use the main thermoelectric process. The main thermoelectric process here includes: furnace, boiler, gas turbine and energy generation by magnetic fluid (hydrodynamic magnet) (MHD).

Therefore, the object of the present invention is to provide a new type of cellulosic lignin fuel whose catalytic performance can meet the market demand for improved combustion characteristics.

Summary of invention

The invention relates to a catalytic fiber lignin fuel, which is composed of cellulose and pelletized lignin, and has a specific surface area of about 1.5-2.5m ² /g, and the average value of the specific surface area is 2.0m ² /g.

Brief description of the drawings

Figure 1 shows a schematic diagram of the biomass cell structure.

Figure 2 shows the steps in a conventional combustion process for solid fuels.

Figures 3a-3e show photomicrographs of the structure of cellulosic lignin according to the invention, and Figure 4 is a diagrammatic representation of an X-ray diffraction pattern of wood, cellulose and cellulosic lignin.

Figure 5 shows the change in enthalpy of reactants during the catalytic combustion of coal, and Figure 6 shows the ratio of burning time to particle size of silk coal. Figures 7a and 7b sequentially represent the power generated in the combustion of cellulosic lignin according to the present invention.

Figures 8-12b illustrate combustion systems and equipment that can be used for currently specified cellulosic lignin fuels.

Detailed description of the invention

After detailed studies, the present inventors have achieved a catalytic cellulosic lignin fuel obtained from biomass, which is surprisingly effective in terms of its combustion. The catalytic fiber lignin fuel of the present invention was prepared by using a reactor described in the Brazilian patent application "Biomass Prehydrolysis Equipment and Method" filed on the same date by adopting the method of biomass prehydrolysis. The indicated prehydrolysis can be performed on any type of biomass, such as wood, bagasse and straw, plant bagasse, bark, pasture, organic fractions of waste, etc.

The pre-hydrolysis method described in the above-mentioned patent application generally includes the biomass unloading step in the screw feeder and in the biomass pre-hydrolysis equipment, and then pressurized operation, including the following steps: 1) pre-hydrolyzing the biomass 2) heating; and 3) pressurization, the method is different in that the prehydrolysis process is carried out simultaneously with the rotary vibration of the biomass prehydrolysis equipment, steam purging and control of temperature, pressure, acid Content, pre-hydrolysis time and liquid/solid relationship, monitor the sugar content through the sugar measuring mechanism until the sugar content reaches about 10Bricks. The following steps are then performed: discharging the prehydrolyzate through a heat exchanger to a storage tank, washing the recovered sugars, and discharging the cellulosic lignin to a mechanical scrubber or carrier, where it is filtered and washed.

Referring again to Figure 1 and Table 1 shown above, it can be seen that according to this method of biomass hydrolysis, the cellulose fibers release is incomplete because half Highest concentration of cellulose. Adopt the prehydrolysis method that the present invention develops, have obtained a kind of product that is about 1.5-2.5m ² /g in specific surface area measured according to BET method at present, specific surface area average value 2m ² /g, and silt number (slush number) is 100, which means that this prehydrolysis method reaches a level where partial separation of giant fibers occurs.

The photomicrographs shown in Figures 3a-3e show evidence of this giant fiber separation. Figure 3a shows the microstructure of catalytic cellulosic lignin after prehydrolysis according to the invention, magnified 1000 times (10 μm scale). Figure 3b shows a 10000 times magnification (1μm scale) of the cell wall showing the middle sheet, while Figure 3c shows a 50000 times magnification (100nm scale) of the cell wall, and Figure 3d shows a 100000 times magnification (10nm scale) of the cell wall. Figure 3e shows the cell wall of the first The microstructure of the second sample, where it is possible to see the spheroidization of lignin.

As can be seen from Figure 4, a combination of disconnected structures, while maintaining the crystallization characteristics of cellulose as indicated by X-ray diffraction, enables cellulosic lignin fuels to achieve the following characteristics:

1 - Due to the maintenance of cellulose crystallization characteristics, it is possible to use hammer milling to realize the grinding of the cellulosic lignin according to the present invention, so that the particle size is reduced to below 200 μm, without intermediate sieving, and low energy consumption (about 12kWh/ t). Because of this feature, the new fuel is called "catalytic" lignin.

2-It is easy to dry and dehydrate in a drum dryer, stove or cyclone separator: according to the present invention, the fiber lignin has a particle size of 200 μm or less, has a completely disconnected structure, and is allowed to dry at 500 ppm moisture and low temperature, that is, 125 ° C (smoke air) for drying.

The water contained in the biomass is one of the worst characteristics for combustion, and the dryness achieved by the cellulosic lignin of the present invention allows the calorific value of combustion to reach 18-20MJ/kg, which is the combustion of biomass with a normal moisture content of 45%. Twice as hot.

Thus, a significant technical advantage obtained with the present invention is that the heat of the flue gas can be used to externally dry the catalytic cellulosic lignin, followed by dry combustion. This option is not feasible for logs.

3- For the powder type, the density of the so-called adapted cellulosic lignin is 600 kg/m ³ and for the unadapted type 450 kg/m ³ . This means that the average energy density is 20 MJ/kg×500 kg/m ³ =10 ⁴ MJ/m ³ . In contrast, the energy density of fuel oil is 40MJ/kg×800kg/m ³ =3.2×10 ⁴ MJ/m ³ , which means that the storage and disposal of the catalytic fiber lignin fuel is only three times that of fuel oil , and it is much easier than disposing of raw biomass (wood and plant residues), which requires large volumes and huge equipment.

4-The fiber lignin of the present invention is batched in the combustion equipment, adopts such as screw feeding device or rotary valve, and according to air: fiber lignin weight ratio is about 3.28: 1 and volume ratio is 1261.6: 1 injection as damping gas (drag -gas) of the air. This gives the cellulosic lignin a characteristic equivalent to gas or liquid in the batching and feeding operation, making the operation much easier than the conventional batching and feeding operation of solid fuels especially for biomass.

5-These microstructural diagrams represent disclosures for 50nm microfibril sizes. This technique establishes a relationship between process (digestion of hemicellulose) and product (disconnected structure of medium specific surface area). It constitutes one of the main novel features of this product and the technology to control the prehydrolysis process in the production of catalytic cellulosic lignin fuels.

6- Table 4a illustrates the physical properties of micropores (active sites) and Table 4b gives the distribution of mesopores and macropores. The former was determined by BET adsorption of _N2 and the latter by Hg porosimetry. The total specific surface area measured by BET is about 2.20 m ² /g, and the specific surface area of macropores and mesopores accounts for a larger part of the total surface area. Using cylindrical symmetrical pores (1=2r), the specific surface area is 1.80 m ² /g calculated from the average pore radius measured by Hg porosimetry. This conclusion is consistent with the low micropore volume (1.1×10 ^-3 cm ³ /g) determined by BET. The distribution of macropores and mesopores has a maximum in the range of 1-5 μm (1000-5000 nm), a size consistent with the micelle void fraction photographed by MEV (Figures 3a, 3b and 3e). The data in Table 4 and the microstructure of the MEV enable the full characterization of the catalytic cellulosic lignin fuels of the present invention. Micropores are determined with an iodine number equal to 100; in the case of catalyzed cellulosic lignin, there are still no test devices capable of estimating the contribution of micropores (2 nm) in combustion.

Table 4a: Micropore Physical Characterization

(active site-φ<2.0nm) sample Crystal Density ⁽¹⁾ (g/cm ³ ) Specific Surface Area ⁽²⁾ (m ² /g) Pore Radius ⁽²⁾ (nm) Micropore volume ⁽²⁾ (×10 ^-3 cm3/g) 1 - Timber 1.284 0.459 0.948 0.217 2-Unground fiber lignin-prehydrolysis time 2a-0.5h (oscillating) 2b-1.0h (oscillating) 2c-1.0h (static) 2d-2.0h (oscillating) 1.3311.3371.3341.351 0.7561.4631.3422.249 0.9800.9050.9700.964 0.3710.5620.6511.080 3-grinding effect 3a-unground fiber lignin 3b-297μm<φ<354μm3c-177μm<φ<210μm3d-125μm<φ<149μm3e-88μm<φ<105μm 1.2521.3531.3681.3751.3721.346 2.4832.7582.0132.1141.9153.179 1.1970.9971.1351.0320.9620.914 1.4961.3751.1431.0900.9211.454 3f-φ＜74μm 4- wood and carbonized fiber lignin 4a- carbonized wood 0.5h4b- fiber lignin, 0.5h4c- fiber lignin 1.0h4d- fiber lignin 2.0h4e- double carbonization 1.3141.2921.3271.3711.421 0.9652.4741.4521.9322.497 1.0241.0141.0021.0091.000 0.4941.2540.7270.9741.248 Table note: (1) Helium hydrometer; device used: Super hydrometer type: 1000 Quantachrome-type: 1.62

(2) BET-adsorption of _N2 ; device used: adsorption meter type: Nova Quantachrome-formula 3.70 Table 4b: Pore distribution (cm ³ /g) of mesopores (2nm<0<50nm) and macropores (0>50nm) ) Mercury porosimeter D, - pore size (nm) Cylindrical geometry hole (r=21)(S/V)=(2πr ³ +πrl)/(πr ³ l)(S/V)=(2/r)S=2V/r M ³ /g) sample mean radius D, <10 10<D,<100 100<D,<1000 10 ³ ×D, <2×10 ³ 2×10 ³ <D, <5×10 ³ Total 3a - Cellulose lignin, unground φ > 2 mm φ > 354 μm 631.21026.2 0.0160.004 0.0780.022 0.2330.084 0.0380.039 0.0560.046 0.4210.197 2.6580.758 3b-297μm<φ<364μm210μm<φ<250μm 883.0987.2 0.9960.002 0.0330.027 0.0950.064 0.0520.048 0.9560.051 0.2320.219 2.9861.755 3c-177μm<φ<210μm149μm<φ<177μm -845.6 -0.003 -0.018 -0.094 -0.062 -0.035 -0.212 -2.004 3d-125μm<φ<149μm105μm<φ<125μm -2230.6 -0.007 -0.025 -0.090 -0.058 -0.049 -0.229 -1.553 3e-88μm<φ<185μm74μm<φ<88μm -1003.2 -0.009 -0.025 -0.091 -0.051 -0.042 -0.210 -1739 3e-φ＜74μm -1715.4 6.006 0.023 0.106 0.163 0.530 0.830 3.876 S = hole area V = hole volume r = hole radius l = hole length

7 - The main application of the cellulosic lignin of the present invention is as fuel for boilers, gas turbines and for energy generation by magnetic fluids (MHD). However, besides use as a fuel, there are several other applications in the following areas: bulk components of animal feed, production of oils and activated carbon by pyrolysis, production of carbon black (incomplete combustion), production of methanol, cellulosic lignin resin acids Salt (agglomerates, MDF-Medium Density Fiber), semi-solid fermentation (fungus, bacteria and enzymes) media, etc.

Although the exact chemical formula of cellulosic lignin according to the present invention may vary, its empirical formula is listed in Table 5 and compared with empirical formulas for wood, biomass components, silk coal and fuel oil, these data provide A good reference for presumably improved effects of currently developed fuels.

Table 5: Chemical formulas of several fuels

Fuel (moisture) Material Fixed carbon Ash content Approximate empirical chemical formula

Volatile content (%) (%) (%)

1. Cork (46%):

Douglas Fir 86.2 13.7 0.1 C _4.4 H _6.3 O _2.5 N _tr

·Pine pine - - - C _4.9 H _7.2 O _2.0 N _tr

Hemlock 84.8 15.0 0.2 C _4.2 H _6.4 O _2.6 N _tr

2. Hardwood (32%):

Poplar - - - C _4.3 H _6.3 O _2.6 N _tr

·American Ash - - - C _4.1 H _7.0 O _2.7 N _tr

3. Bark

Oak - - - C _3.3 H _5.4 O _3.1 N _tr

·Pine - - - C _4.5 H _5.6 O _2.4 N _tr

4. Timber

Dry (17%) - - - C _4.4 H _6.0

O _2.4 N _0.02 (H ₂ O) _1.1 ·Water (50%) - - - C _4.4 H _6.0

O _2.4 N _0.002 (H ₂ O) _5.6

Table 5 - Continued

Fuel (moisture) Volatile content of material Fixed carbon Ash content Approximate empirical formula

(%) (%) (%)

5. Biomass components

· Cellulose (C ₆ H ₁₀ O ₅ ) _n

· Hemicellulose (C ₅ H ₁₀ O ₅ ) _n

· Lignin (C ₁₀ H ₇ O ₄ ) _n

· Catalytic cellulosic lignin C _5.5 H _4.2 O _1.0 N _tr

· Cellulosic coal C _6.7 H _3.3 O _1.0 N _tr

6. Tar: C _4.7 H _5.0 O _3.0 N _tr

7. Silk coal:

·Lignite (3-7%) - - - -

·Sub-bituminous coal

A(14%) - - - - -

B(25%) 40.7 54.4 4.9 C _5.0 H _4.8 O _1.0 N _tr

C(31%) - - - -

·bituminous coal

Low volatile 17.7 71.9 10.4 C _6.7 H _4.3 O _0.14 N _0.11

Medium volatile content - - - -

High Volatile 6.4 81.4 12.2 C _6.8 H _2.3 O _0.12 N _0.09

Anthracite 6.4 81.4 12.2 C _6.8 H _2.3 O _0.12 N _0.06

8. Oil (APF-A1) - - - C _7.3 H _11.1 O _0.09 N _0.02

As can be seen, the biomass is low in carbon (4.3 moles per chemical-gram), intermediate in hydrogen (6.5 moles per chemical-gram), and high in oxygen (6.5 moles per chemical-gram). Silk coal is high in carbon (6.5 moles per chemical-gram), low in hydrogen (4.3 moles per chemical-gram), and low in oxygen (0.15 moles per chemical-gram). Catalytic cellulosic lignin according to the invention is in the middle, with carbon (5.5) and hydrogen (4.2) contents close to that of silk coal, but intermediate oxygen content (1.8 moles per chemical formula-gram). In fact, the catalytic cellulosic lignin obtained in the 20-minute prehydrolysis was close to that of lignite, which took millions of years to form.

Another important advantage of the currently developed cellulosic lignin fuel is that it has an extremely low ash content and therefore, when treated in prehydrolysis with deionized water, meets e.g. the requirements of a clean fuel for gas turbines (Na+<5ppm) . This is due to the solubilizing effect _{of the} prehydrolysis method on K in water-soluble _K2SO4 , which is later leached in _the washing step. All impurities contained in wood are reduced, and even those impurities in higher levels, such as Ca, Mg, Al and Si present in eucalyptus, do not cause thermal corrosion of superalloys of gas turbines. Gas cyclone separation of fuels according to the invention demonstrated high ash reduction efficiency to the levels required for gas turbines (total particles < 200 ppm and fraction of particles > 5 μm in diameter less than 8 ppm).

With regard to the improved characteristics of the cellulosic lignin fuels of the present invention, which bring significant advantages over conventional fuels to the combustion process, several points should also be emphasized.

As mentioned earlier, in the solid high-temperature pyrolysis zone of the combustion process, high temperature favors the production of volatile compounds and low temperature favors coal production. As shown in Table 2 above, since the pyrolysis products of cellulose and xylan lead to high tar content, the post-combustion of wood is close to the post-combustion of oil. However, there is no xylan in the catalytic cellulosic lignin according to the invention, which would lead to a lower coal content in this zone. In addition, it should be pointed out that in the production process of catalytic fiber lignin fuel of the present invention, the spheroidization of lignin is beneficial to the generation of volatile matter and the reduction of coal content. Furthermore, given the effect of moisture on pyrolysis of particulates, catalyzed cellulosic lignin fuel maximizes the combustion temperature, increases the content of volatiles, and reduces the amount of coal produced because it provides a moisture-free and low-ash coal burning potential.

Other technical advantages manifested according to the present invention are clearly seen in the pre-combustion reaction of cellulosic lignin fuels, in the primary combustion reaction as well as in the post-combustion reaction.

During this pre-combustion step, the reduction of ash and moisture observed in the case of catalyzed cellulosic lignin and the absence of xylan favor the formation of CH ₄ , a product of R"cellulolysis, Not conducive to C ₂ H ₆ (from the decomposition products of hemicellulose, which are not present in cellulosic lignin).In the primary combustion process, the combustion of cellulosic lignin occurs at higher temperatures, as does the decarboxylation of acetic acid due to ring cleavage and acetaldehyde decarburization formation of _CH4 . In fact, this explains why the combustion of catalyzed cellulosic lignin is similar to the combustion of natural gas and volatile liquid fuels. Finally, during the post-combustion step, the C:H ratio of catalyzed cellulosic lignin It is 1:0.76, that is to say, it is close to silk coal, but not close to wood. But the average oxygen content is conducive to the formation of CH ₄ , CO ₂ and CO, thus strengthening the catalytic activity of lignin for cellulose high explanation.

In order to fully understand the similarity of the catalytic fiber lignin combustion characteristics of the present invention compared with silk coal, in view of the significance of the fiber lignin combustion of the present invention, the modern theory (Essenhigh) of porous particle combustion is listed below.

Mass loss rate: m=m(a,σ), where m=sphere mass, a=particle radius, d=2a=particle diameter, σ=particle density and m=(4/3)πa ³ σ. $\frac{\mathrm{dm}}{\mathrm{dt}}=\frac{\&PartialD;m}{\&PartialD;a}\frac{\mathrm{da}}{\mathrm{dt}}+\frac{\&PartialD;m}{\&PartialD;\mathrm{\&sigma;}}\frac{\mathrm{d\&sigma;}}{\mathrm{dt}}$ $\frac{\mathrm{dm}}{\mathrm{dt}}=4\mathrm{\&pi;}{a}^2\mathrm{\&sigma;}\frac{\mathrm{da}}{\mathrm{dt}}+\frac{4}{3}\mathrm{\&pi;}{a}^3\frac{\mathrm{d\&sigma;}}{\mathrm{dt}}$ $R_{\mathrm{the\; s}}=\frac{\mathrm{dm}/\mathrm{dt}}{4\mathrm{\&pi;}{a}^2}=\mathrm{\&sigma;}\frac{\mathrm{da}}{\mathrm{dt}}+\frac{a}{3}\frac{\mathrm{d\&sigma;}}{\mathrm{dt}}=R_e+R_i=R_e\&lsqb;1+\frac{R_i}{R_e}\&rsqb;$ $\frac{R_i}{R_e}=\frac{a}{3\mathrm{\&sigma;}}\frac{\mathrm{d\&sigma;}}{\mathrm{da}}=\frac{1}{3}\frac{d\left(\ln \mathrm{\&sigma;}\right)}{d\left(\ln a\right)}$

R _s = mass loss rate on the outer surface of the particle (g/cm ² s), and R _i is the mass loss rate on the inner surface. The above formulas are a set of inexact differential equations, which cannot be integrated due to the lack of relationship between σ and a (integration method).

Essenhigh (1988) suggested using Thiele's (1939) catalytic formula as an integral method for R _s

where α = 0 represents the density, σ is the outer surface combustion related constant, and α → ∝ represents the constant diameter associated with the inner surface combustion (this concept is similar to catalysis on the outer or inner surface).

Calculate the R _i /R _e relationship according to the following formula: $\frac{R_i}{R_e}=\frac{R_i}{R_{\mathrm{im}}}\frac{R_{\mathrm{im}}}{R_e}=\mathrm{\&eta;}\frac{R_{\mathrm{im}}}{R_e}$

where R _im is the maximum internal loss rate and η=R _i /R _im is the Thiele efficiency factor (0<η<1), which represents the relationship between the real internal loss and the maximum possible internal loss (for large particles or particles with low porosity , the internal mass loss is negligible and η→0, while for fine and high-density particles, the internal mass loss is a maximum and η=1).

Define S _v as the inner surface area of the unit volume unit V _p ((cm ² /cm ³ )=1/cm) and S _p as the outer surface area of the particle, then the ratio of R _im / _Re is based on the following relationship between the inner and outer areas: $\frac{R_{\mathrm{im}}}{R_e}=\frac{V_p{S}_v}{S_p}=\frac{\frac{4}{3}{\mathrm{\&pi;a}}^3{S}_v}{4{\mathrm{\&pi;a}}^2}=\frac{a{S}_v}{3}$ $\frac{R_i}{R_e}=\frac{a}{3}{S}_v\mathrm{\&eta;}=\frac{1}{3}\frac{d\left(\ln \mathrm{\&sigma;}\right)}{d\left(\ln a\right)}=\frac{\mathrm{\&alpha;}}{3}$ α＝αS _v η

For silk coal, α ranges from zero to 3, reaching a value of 6 in some cases. For catalytic cellulosic lignin fuel, we have _Sv = _σSg , where _Sg is the internal surface area per unit mass, and the following values are for 200 μm particles: S _g m ² /g 0.01 0.1 0.2 0.3 0.4 0.5 1.0 10.0 m ² /kg 10 10 ² 2×10 ² 3×10 ² 4×10 ² 5×10 ² 10 ³ 10 ⁴ α＝aσS _g η 1 10 20 30 40 50 100 1000 (σ/σ ₀ )=(d/d ₀ ) _α p/(d/d ₀ )=0.9 0.9 0.349 0.122 0.042 0.015 0.005 2.7×10 ^-5 1.7×10 ⁴

This means that for a specific surface area greater than 0.4 m ² /g (α = 40), the combustion of catalytic cellulosic lignin fuel is mainly on the inner surface, and its particle size remains approximately constant, while its density changes (section-1 ^a region combustion), characterizing the new invention as a fully catalyzed macrofuel obtained from the prehydrolysis of natural biomass. Specific surface area tests (BET, mercury and MEV porosimetry) indicated an average value of 2.0 m ² /g, resulting in α=200. Liquid fuel particles burn from the outer surface (α = 0-3 ^a zone), silk coal particles have part of the internal combustion (0 = or < α = or < 3-2 ^a zone).

For silk coal, α=S _v /γ, where γ is the Thyele parameter, obtained by the following formula:

λ=(S _v k/ρD _e ) ^1/2 ; α=(ρD _e S _v / k) ^1/2

where k = reaction rate constant, p = reactant gas density and De = internal diffusion coefficient. For catalyzed cellulosic lignin, these parameters do not need to be determined individually, as they combine to give a high alpha value (alpha = or >100).

- In catalytic combustion, oxygen directly attacks carbon atoms in a two-stage reaction (adsorption-desorption), as illustrated in FIG. 5 . Oxygen is adsorbed and desorbed to form _CO2 or CO, which is then desorbed again. The components and products of the reaction are C, O ₂ , CO ₂ , H ₂ O, H ₂ and CO, according to the following reaction:

where C _f represents free sites, C(O) represents chemisorbed oxygen atoms and ki is the reaction constant. The volatiles (CO, H ₂ ) formed by the catalytic combustion complete their combustion extraparticles in a very short time (3 milliseconds). The measured burning time is the burning time measured by the adsorption and desorption method, and is equal to or shorter than 20 milliseconds (0.02 seconds).

The burning times measured as isolated particles and dust for silk coal, liquid (oil) and for catalyzed cellulosic lignin fuels are illustrated in Fig. 6 and the chemical formulas used in the corresponding calculations are listed below.

Appendix l: Burn Time

la - combustion of coal

burn time

i) At constant density: $t_b=\frac{{\mathrm{\&rho;}}_{0}R{T}_m}{96\mathrm{\&phi;D}{p}_z}{d}_0^2$ ii) At constant diameter: $t_b=\frac{{\mathrm{\&rho;}}_{0}R{T}_m}{144\mathrm{\&phi;D}{p}_z}{d}_0^2$ Where: ρ ₀ = initial particle density≌1000kg/m ³ R = universal gas constant = 0.8106m ³ atm/(kmolK)T _m = average temperature = 1600K

D = diffusion coefficient = 3.49×10 ^-4 m ² /s

_Pg = partial pressure of oxygen = 0.2 atm

φ = reaction order = 2

d ₀ = primary particle size (m)

1b = liquid burning

burn time

t _b =d ₀ ² /λ

in:

d ₀ = primary particle size

λ = vaporization rate = (10±2)×10 ⁻³ cm ² /s (for combustion of hydrocarbons in air).

For the first form, the burning time is shorter than for silk coal, since it is a very reactive fuel. For the powder "smoke" type, due to the radiation between the particles, the heat loss of the energy transfer is reduced, and the burning time is shortened, which is the same as the value of the volatile liquid. One way to analyze this problem is to use Krishna and Berlad's energy balance for the ignition of silk coal dust. $\left(\mathrm{const}\right)T_i^{\mathrm{\&beta;}-1}=\frac{{\mathrm{\&lambda;}}_0/a}{1+R^2\mathrm{D.}/a^2\mathrm{\&sigma;}}$

where the first term is the energy generation rate, a is the particle radius, R is the soot radius, ρ is the particle density, D is the soot density, _λ0 is the air thermal conductivity and β is the empirical coefficient. As long as R ² D/a ² σ<<1, aT ₁ β ^-1 = (constant). If R ² D/a ² σ>>1, then T ₁ β ^-1 = (constant) a. The latter is in line with world experience, which recommends grinding silk coal at a temperature not higher than 70 °C to avoid incineration of fine dust in the mill. For the injection of catalytic cellulosic lignin fuel, we have R = 0.1 m, a = 100 x 10 ^-6 m, σ = 500 kg/m ³ , D = 0.4 kg/m ³ , resulting in R ² D/a ² σ = 800 >>1. The smaller the particle size, the lower the ignition temperature of the powder soot. The theoretical ignition temperature of the soot is between 300-500°C for silk coal and about 350°C (pyrolysis temperature) for catalytic cellulosic lignin. Catalytic cellulosics The presence of oxygen in the lignin fuel molecule favors a combustion process similar to that of silk coal (but with a higher reactivity and higher ignition temperature), whereas wood combustion has five steps and is severely limited by the presence of water .

To determine the combustion characteristics, catalytic fibrous lignin particles of different diameters were burned by laser ignition and irradiance measurement with photodiodes. The results are shown in Figures 7a and 7b, where two conditions can be seen, namely: 1) above 250 μm, the combustion is of the conventional type (limited by intra- and extra-particle mass transfer), and 2) below 250 μm, Combustion is not mass flow limited ( _O2 adsorption-CO desorption method). These two conditions regulate Thiele's catalytic combustion. Attention is paid to the importance of maintaining the crystalline character of the cellulose during prehydrolysis in order to cheaply grind the fibrous lignin particles to less than 250 μm.

a) Conventional combustion (φ>250 μm): Catalyzed cellulosic lignin is dried outside the combustion equipment, and there is no drying zone. Heating is rapid, volatiles production is maximized, and coal formation is minimized. The catalyzed cellulosic lignin does not contain xilan, and its solid high-temperature pyrolysis is dominant, that is to say, acetic acid, acetaldehyde and coal are produced by ring cleavage, and CH ₄ , CO ₂ and CO are produced with decarburization of acetic acid and decarboxylation of acetaldehyde. The volatile primary and secondary combustion zones are the same as previously described.

b) Catalytic combustion (φ<250μm): Pre-hydrolysis replaces biomass in silk coal combustion. The main feature is that the combustion is more limited by the mechanism of oxygen transfer into the catalytic cell lignin process and the CO on it due to the particle microstructure. In this approach, physisorption (O ₂ ) and chemisorption (O) and Boudouard reactions on the active sites are favored. The reaction of the hydroxyl groups causes rapid reactions in the heating zone and in the high temperature pyrolysis zone of the solid. Catalytic combustion generally occurs at the average inner surface (2.0 m ² /g), with a minor contribution from the outer surface of the particle (0.1 m ² /g). The skeleton structure of catalytic cellulosic lignin is a kind of skeleton structure that can be partially burned while keeping the particle diameter roughly constant and particle density reduced. When the partial wall thickness reaches a critical dimension, particle (sublimation) collapse then occurs. Thus, this process eliminates the formation of cinders, resulting in complete combustion.

The equipment that can be used in the present invention to catalyze the combustion of cellulosic lignin depends on the specific type of combustion used. In this regard, the main methods of biomass combustion are: pile combustion, jet distributor combustion, suspension combustion and fluidized bed combustion. From an industrial point of view, jet distribution burners are the most important. The first two features are completely physically separated among the five combustion zones. In the suspended combustion of dry biomass particles (<2mm, TU<15%), all "zones" appear sequentially in the air. Suspension combustion is closest to the combustion of liquid fuels. This is the case for the currently proposed cellulosic lignin, which is close to the combustion of gases and liquids, since it is a catalytic combustion.

Combustion in a fluidized bed uses air-suspended sand or lime to keep the fuel within the bed. All reaction zones are carried out in the same place (in fact inseparable). The combustion efficiency is low due to the excess air (100-140%) necessary to maintain the fluidized bed and the need to keep the temperature below the ash melting point so that the fluidized bed does not collapse. In the case of the catalytic cellulosic lignin of the present invention, the suspension combustion can be accomplished with stoichiometric air, without limiting its temperature because of its extremely low ash content. The three main parameters in combustion are effective heat, thermal efficiency, and combustion temperature.

Hv=CCS-PT; η=[1-(PT/CCS)]×100

Among them, CCS is the high heat capacity, and PT is the chimney heat loss, ash (including unburned carbon) and radiation. The chimney heat loss is given by: $\mathrm{PT}=\underset{i=1}{\overset{\mathrm{no}}{\mathrm{\&Sigma;}}}{m}_i\left({\mathrm{Cp}}_i\mathrm{\&Delta;T}\right)+m_{m_{i}p}{\mathrm{\&lambda;}}_{m_{i}p}$

Where m _i is the number of moles of flue gas (CO ₂ , O ₂ , N ₂ , H ₂ O), Cp _i is the heat capacity of each species, ΔT is the temperature difference between the flue and the environment, m _H2O is the molar amount of water , and λ _H2O is the molar heat of vaporization of water.

Radiation losses are about 4%, other losses (ash, unburned carbon) about 2%. Wood with 50% moisture burns 68% efficiently; 17% moisture burns 79% efficiently, while catalyzed cellulosic lignin burns 85% (close to that of silk coal) because of the absence of moisture , ash and excess air. The permissible temperature of the catalytic fiber lignin fuel of the present invention is close to the adiabatic temperature (1920K), but the temperature of the boiler steam generation tube is limited to 840K.

The heat release rate for the different combustion methods is given by I = h dW/dt, where I is the flame intensity, dW/dt is the change in weight as a function of time, and h is the heat of combustion. Table 6 shows several rates for different combustion methods:

Table 6: Heat Release Rates for Different Combustion Methods burning method wood silk coal pine wood burning 8.5GJ/m ² h Slanted Grid 3.5GJ/m ² h Jet distribution 10.4GJ/ ^m2h 8.8GJ/m ² h suspend 550GJ/ ^m2h fluidized bed 470GJ/ ^m2h

Catalytic cellulosic lignin is slightly more reactive than biomass (no water, larger specific surface area), with twice the heat of combustion, resulting in twice as high a heat release rate as wood. For example, the combustion heat of catalyzed fiber lignin of 9kg/h in suspension combustion with φ=2cm and L=50cm volume is 20MJ/kg, namely (9×20/(π×(0.01) ² ×0.5)=1.146 GJ/ m ³ h.

The device examples listed below fully illustrate the invention in a better way. However, the data and procedures described relate to only a few embodiments of the invention and should not be construed as limiting the scope of the invention.

Complete characterization of catalyzed cellulosic lignin fuels involves elements of cellulosic lignin as raw material, combustion specific characteristics, and fuel handling and control equipment.

Figure 8 shows a feeding system consisting of a fiber lignin storage tank (8.1), a rotary valve or screw feeder (8.5 and Figures 9 and 10) for dosing fiber lignin, an air/fiber lignin two-phase Feed pipes for flow (rate 3.28:1 (weight)) (8.6) and facilities in boilers and furnaces (pressure close to atmospheric pressure, T = 1900 ° C), in gas turbines (pressure 7-14 atm, T =600-1100°C). Cellulose lignin tanks can be fixed (preferably upright cylinders) or mobile (mounted on a cart, similar to tanks for transporting animal feed or cement). Since cellulosic lignin tends to settle, tanks are preferably fitted with conical or flat bottoms with rotating shovel type (8.2, 8.3, 8.4) powder handlers, screw feeders, or with movable air lines. At the outlet of the rotary valve or doser used to dose the cellulosic lignin, drag air to the two-phase flow was injected at a ratio of 3.28:1. The two-phase flow can consist of metal or plastic hoses, with the air/cellulosic lignin mixture behaving like a gas or a liquid. At low pressure, the air/cellulose lignin mixture has an energy density of 7.14MJ/m ³ compared to 32.9MJ/m ³ for natural gas and 28.0MJ/m ³ for fuel oil, still allowing compactness, simple installation and obvious Length of piping to meet the layout of factories, thermal power stations, etc.

The screw feeder shown in Figure 9 consists of a main body (9.1), casing (9.2), screw feeder (9.3), powder baffle (9.4), bearing (9.5), flange (9.6), drive wheel (9.7) and air jet (9.8) for two-phase flow. The batching of cellulosic lignin is done by turning the screw feeder and changing its diameter, and it is generally used at low capacity (<150kg/h). The elimination of the influence of the pressure difference between the fiber lignin storage tank and the damping air in the screw feeder conveying powder ingredients is realized by utilizing the length pipe resistance of the screw feeder between the storage tank body and the two-phase flow damping air. The rotary valve indicated in figure 10 is commercially available with a capacity higher than 150 kg/h, consisting of a main body (10.1), shovel (10.2), drive shaft (10.3), viewing window (10.4) and possible cooling (10.5). Use the rotation, valve diameter and length to control the batching amount.

burner

Direct use of burners in boilers and furnaces is possible because the fiber lignin has a low ash content (<0.2%) and the material is already in equipment for removing residual ash. For applications in gas turbines, the following measures are necessary: a) The combustion chamber has primary air injection (stoichiometric combustion) and secondary air injection (to prevent ash from the combustion chamber to the cyclone separator and to cool the combustion gases , to reduce its temperature to the operating temperature of the turbine); b) gas cleaning cyclones (to remove particles); and c) possible ceramic filters for high temperature turbines (1100°C - single crystal superalloys) , these filters are integral to polycrystalline superalloys or have directional solidification. For the catalytic fiber lignin fuel with a total particle content of 200ppm, the particle diameter>5μm in the combustion gas is below 8ppm, and the specification of (Na+K)<5ppm has been reached, and no ceramic filter is needed.

axial burner

Figure 11 shows an example of an axial burner to characterize the combustion of catalyzed cellulosic lignin. Ignition can be done in several ways, such as GLP, micro torches of natural gas etc., electric arc, electric resistance or hot gas tube. The fact of ease of operation, automation and low cost favors blowtorch ignition with GLP, natural gas (consumption 0.022 kg GLP/kg cellulignin, corresponding to 5% of the heat capacity of the burner). It should be pointed out that there are two factors related to the ignition of catalytic cellulosic lignin: first, it is necessary to heat the catalytic cellulosic lignin to the pyrolysis temperature (350°C); Cellulose lignin is safe to operate. The practical application may be any type of burner (axial, swirler, cyclonic, etc.).

The axial burner consists of a fixed table with or without cooling (11.1), fiber lignin injectors (11.2), stoichiometric combustion-air injectors (11.3), ignition torch fixtures with or without cooling (11.4), Ignition torch (11.5) for GLP or natural gas, etc., observer window (11.6). The ignition torch is as small as commercially available because of the catalytic properties of the cellulignin for instantaneous ignition and propagation of the air/cellulo-lignin two-phase flow. The power of the ignition torch is about 5% of that of a low power (50kw) burner, and the percentage tends to be negligible for a high power burner. For a two-phase flow with a velocity of 8.5 m/s and a diameter of φ = 16.5 mm, the ignition propagation length is 100 mm, and the ignition time is 0.012 seconds = 12 milliseconds. Burn completely under length 0.7m, residence time 1/(8.5/2)=0.16 second=160 milliseconds (people have adopted average speed 8.5/2=4.25m/s, because the ejection velocity 8.5m/s of flame beginning, flame The final velocity is actually zero). The relationship of resistance time/ignition time is about 10 times. The ignition time of the catalytic cellulosic lignin is close to the gas ignition time, about 3 milliseconds.

Generally, silk coal and liquid fuel have a very long flame due to their long combustion time (see Figure 6), so an axial swirler type burner is required to shorten the flame length. The catalytic properties of cellulosic lignin allow the use of axial burners with relatively short flame lengths. Since it is necessary to pyrolyze the catalytic fiber lignin at 350° C. to achieve complete safety in the disposal of the catalytic fiber lignin (non-arson and non-explosive fuel), the extinguishment of the ignition blowtorch will cause the flame of the catalytic fiber lignin to go out. Catalytic cellulosic lignin does not contain the hemicelluloses responsible for the arson characteristics of straw-type biomass (pyrolysis temperature = 200°C), and it does not pyrolyze at low temperatures, so it does not have the arson characteristics of gas and liquid fuels (low flash point) . On the other hand, above 350°C, its combustion is catalytic and its ignition time is close to that of a gas.

gas turbine

For the application of fiber lignin burners in gas turbines, two additional steps are required, namely: cooling the gas and cooling the cyclones to reduce particulates. Figures 12a and 12b illustrate the burner, cyclone separation and particle collector with horizontal or vertical components for such cellulosic lignin. It includes burner (12.1), combustion chamber (12.2), cooling air inlet (12.3), cooling air chamber (12.4), homogenization section (12.5), cyclone separator (12.6), particulate collector (12.7 ) and the piping (12.8) communicating with the turbine. For the vertical position, an ash collection chamber (12.9) is added before the combustion gas is passed into the cyclone to collect the molten ash during the stoichiometric combustion process.

The burner shown is made of stainless steel, except for the combustion chamber, which is made of a superalloy due to the high temperature (1920°K) and is cooled with cooling air. A portion of the cooling air penetrates the holes drilled in the combustion chamber wall, forming a surrounding layer of damping air that drags slag and particulates.

One of the main features of gas turbines is their versatility for fuel, operable gases such as natural gas, evaporated oils and process gases (refinery, blast furnace blowers and gasifiers); liquids such as clean liquids, i.e. volatile naphtha oils, light distillates (diesel, kerosene) and viscous and heavy residues; and solid particles. Liquid fuels with a high ash content (crude oil and residual oil) pass through purification equipment before they can be used.

Table 7 illustrates the properties of three types of conventional fuel and catalytic cellulosic lignins. Catalyzed cellulosic lignin is placed between natural gas and light distillates (clean fuels) and heavy distillate blends and low ash crude oils. It does not contain V ₂ O ₅ , WO ₃ , MO ₃ or Pb, and has an extremely low S content. The (Na+K) concentration in clean catalyzed fiber lignin was close to that in clean fuel, but for normal catalyzed fiber lignin it was close to the value in high ash heavy residue (Table 8). Prehydrolysis with deionized water is an efficient process for producing clean catalytic fibrous lignin as fuel for gas turbines. The only parameter other than clean fuel conditions was total ash (<0.1%). However, these were significantly reduced in the cyclone, reaching <200 ppm total particulate content and less than 8 ppm particle size > 5 μm.

Natural gas fractions require no fuel treatment. For heavy-distillate mixtures, low-ash crude oils, and especially high-ash heavy residues, fuel scrubbing is required based on its water solubility for sodium, potassium, and calcium. There are four conventional washing methods, that is, centrifuge separation, direct current (removal), alternating current (removal) and hybrid (removal) methods. Catalytic cellulosic lignin does not require any washing method used in reducing crude oil and residue (Na+K) content from 100 ppm to 5-0.5 ppm.

Table 7: Properties of fuels nature Distillates and naphtha Catalytic Cellulose Lignin A mixture of distillate oil and low ash crude oil Libyan typical crude oil High Ash Crude Oil and Heavy Residue kerosene #2 Oil #2 JP-4 clean usually low ash crude oil Typical Libyan Crude Oil heavy distillates Flash point (°C) 54/71 48/104 66/93 ＜TA(1) 350(2) 350(2) 10/93 - 92 79/129 Flow point (°C) -45 -48/-12 -23/-1 - Any(3) Any(3) -9/43 20 - -9/35 Viscosity Centistorr 38°C 1.4/2.2 2.482.67 2.0/4.0 0.79 (4) (4) 2/100 7.3 6.20 100/1800 SSU - 34.4 - - - - - - - - Grau API - 38.1 35.0 53.2 - - - - - - Secol Desn.at 38℃ 0.78/0.83 0.85 0.82/0.88 0.7545(5) 0.50 0.50 0.80/0.92 0.84 0.8786 0.92/1.05 Calorific valueMJ/kg 44.5/45.5 42.3 43.9/45.3 20.0 20.0 43.9/44.8 42.2 42.1 42.3/43.7 Ash 1a5 0.001 0a20 - 1000 2000 20a200 36 - 100/1000 coal residue 0.01/01 0.104 0.03/0.3 - 0.3/3 2/10 - - sulfur(%) 0.01/0.1 0.164a0.293 0.1/0.8 0.047 <80ppm 280ppm 0.1/2.7 0.15 1.075 0.5/0.4 hydrogen 12.8 /14.5 12.83 12.0/13.2 14.75 4.3 4.3 12.0/13.2 - 12.40 10.0/12.5 Na+K(ppm) 0/1.5 - 0/1.0 - 5 <60 0/50 2.2/4.5 - 1/350 vanadium 0/0.1 - 0/0.1 - 0 0 0/15 0/1.0 - 5/400 lead 0/0.5 - 0/1.0 - 0 0 - - - 0/25.0 calcium 0/1.0 0/2.0 0/2.0 - <500 500 - - - 0/50 nature Distillates and naphtha Catalytic Cellulose Lignin Distillate mixtures and low pressure crude oil High Ash Crude Oil and Heavy Residue warm up fuel none none have have atomize Mechanical/Low Pressure Air none low pressure/high pressure air high pressure air to distill none none There are some have Inhibitor none none (limited) limited often used washing turbine none none Yes (except distillate oil) have initial fuel naphtha Ignition (GLP, Natural Gas, Heated Tubes, Resistance) certain fuels often used cost higher in the middle in the middle lower illustrate Low quality distillates, ash free Porous powder, limited ash content, can be reduced by cyclone separator Low ash, limited amount of dirt High Ash Low Volatility ASTM standard 1GT, 2GT, 3GT (3GT) 3GT 4GT Turbine inlet temperature higher in the middle in the middle Low Table 8-Inorganic impurities (mg/g) of eucalyptus wood, catalytic fiber lignin and prehydrolyzate Ca K Na Mg P al Si mn Fe Zn S Eucalyptus 560 400 <140 160 170 50 <120 20 10 not detected 140 Cellulose Lignin Usually (1) 500 <60 <140 <40 10 <40 <120 <4 <10 <6 <80 Cellulose lignin rye (limpa) (2) <53 <5 <1 <60 <2 <40 <120 <2 <7 <4 <80 Prehydrolyzate (3) 260 370 80 140 65 10 25 20 8 5 1950 Note:

(1) Fiber lignin treated with filtered tap water, X-ray semi-qualitative analysis

(2) Cellulosic lignin treated with deionization, X-ray semi-qualitative analysis, except for K (with ICP/AES) and for Na (AAS-flame)

(3) Since there was no analysis of initial water and wash water, no mass balance was performed.

For gas turbines, fuel levels are usually specified. In the case of catalyzed cellulosic lignin, this specification should be made on a combustion gas level or on a "fuel equivalent" basis because of the purification effect of a cyclone separator attached to the burner outside the turbine.

The effect of (Na+K) content (ppm) on the working temperature of Iconel superalloy 718 is listed below: (Na+K)ppm 0.33 2.28 3.70 4.89 5.65 temperature(℃) 927 871 815 760 704

This catalytic cellulosic lignin fuel allows operation between 800-830°C. The overlay is used to increase the strength of the superalloy against hot corrosion. Table 8 shows the main types of coatings obtained by diffusion (Al, Pt, Rh, NiCrSi) and coating (Co, Cr, Al, Y) methods. Various methods of depositing the coating were used, namely plasma spraying, sputtering, electron beam vapor deposition (PVD) and sputtering. This hot corrosion resistance is currently limited by the coating and not by the base metal of the turbine rotor and stator.

However, using plasma or EB/PVD protection, it can even reach 16000h of operation under harsh conditions.

The main requirements for gas turbine fuels are: calorific value, cleanliness, corrosivity, deposits/blockages and accessibility. Clean catalyzed cellulosic lignin fuel obtained from biomass prehydrolysis with deionized water meets all the above requirements.

Table 9: Protective layers (overlays) for turbines Protection specification elements in the shield deposition method typical application Combustion chamber (870°C) performance (hours) UC al PC Co-based stator 870 Al, Si PC Basic part Ni RT-5 Al, Cr DPC Ni base stator RT-17 Al, Ni DPC Thorium doped Ni RT-19 al DPC Co-based stator (for high temperature use) RT-21 Pt,Al PC Ni stator and rotor 800 RT-22 Rh, Al EP/PC Ni-based rotor 5000 BB Pt, Rh, Al EP/PC Ni and Co based stator and rotor RT-44 Co, Cr, Al, Y EB/PVD Co-based stator Overlay Ni, Co, Cr, Al EB/PVD Overlays for various purposes Plasma (composite plasma) 18000 (sputtering)

table note

PC-pack cementation (pack cementation); DPC-double pack cementation (doublepack cementation); EP-electroplating; EB-electron beam; PVD-physical vapor deposition

Claims (8)

1. A catalytic fiber lignin fuel, characterized in that it is composed of cellulose and pelletized lignin, and its specific surface area is about 1.5-2.5m ² /g. 2. Catalytic cellulosic lignin fuel according to claim 1, characterized in that it consists of cellulose and pelletized lignin with an average specific surface area of about 2 ^m² /g. 3. Cellulosic lignin fuel according to claim 1 or 2, characterized in that it has a calorific value of combustion of about 18-20 MJ/kg. 4. Cellulosic lignin fuel according to any one of claims 1 to 3, characterized in that it is ground to a particle size of 250 mm or less. 5. Cellulosic lignin fuel according to any one of the preceding claims, characterized in that its ignition time is equal to or shorter than 20 milliseconds (0.02 seconds). 6. Cellulosic lignin fuel according to any one of the preceding claims, characterized in that it has a vaporization temperature of about 350°C. 7. Cellulosic lignin fuel according to any one of the preceding claims, characterized in that its (Na+K) content is lower than or equal to 5 ppm. 8. Cellulosic lignin fuel according to any one of the preceding claims, characterized in that it produces combustion gases with a total particle concentration of less than 200 ppm and a particle concentration of less than 5 nm in diameter of less than 8 ppm.

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